Random shutdown (possible power supply problem?)

[pointy shadow]

Hi there,

This morning my PC randomly decided to switch itself off. I have XP Auto shutdown disabled so if there is a hardware problem it should display a BSOD rather than shut the system down.

I have 2 x 512MB of RAM, P4 3.2Ghz (775) on an ASRock 775VM800 mobo, 3 IDE HDs, 1 SATA HD all powered with a Thermaltake 400w PSU.

My line of thinking is that since there was no BSOD displayed it wont be a memory or CPU problem and is either the mobo or the PSU.

After the shutdown I have to remove the power cable from the PSU a couple of times before the PC will boot so thats flagged up a PSU problem to me.

I ran Sisoft Sandra and the following info is taken from the "Burn in" report:

CPU Voltage 1.33v
+3.3v 3.42v
+5v 5.19v
+12v 11.31v
-12v 0.39v
-5v 1.69v

Are the values for -12 and -5v correct or do they look suspect?

Also, after I turned the PC off this morning it appeared that the chassis (Thermaltake Xaser) was still powered up as the front "Thermaltake" blue logo was lit up but the monitor was flashing as though it was powered off. All this was going on when I couldnt hear my PSU running.

Does anyone have any suggestions as to what they think might be going wrong? Personally I reckon its the PSU but I would appreciate some other input.

Thanks for your help

 

[pointy shadow]

Thanks for your reply.

After I posted the PC decided to shutdown again then about 5 mins later it powered itself back up! I was sitting there going "WTF?" to myself and decided that it has to be the PSU.

I have managed to get a loan of a PSU from a guy I know and so far there has been no reboots and thats about an hour now that the new PSU has been in and fingers crossed all is OK.

If, on the other hand, it does it again then I am lost as to what it can be...